Trial Year Study period Interval Radiotherapy schedule Chemotherapy schedule Delay reason pCR definition Quality score (out of 9)
Moore et al. [6 ] 2004 1980–2002 44 days 50.4 Gy, 46.8 Gy in twenty-six 1.8 Gy fractions 5-FU/LV or irinotecan NA Tumors that were ypT0N0, or only acellular pools of residual mucin were noted 7
Tran et al. [7 ] 2006 1997–2004 8 weeks 45–50.4 Gy 5-FU According to the surgeons’ preference and because it was typically influenced by tumor size/bulk and the perceived need for tumor shrinkage for resectability and/or sphincter salvage NA 7
Lim et al. [8 ] 2008 2002–2006 5, 6, and 7 weeks 50.4 Gy, 45 Gy in twenty-five 1.8 Gy fractions over 5.5 weeks 5-FU/LV or capecitabine or irinotecan/capecitabine According to the surgeons’ preference and their policy regarding the timing of operation NA 7
Tulchinsky et al. [9 ] 2008 2000–2006 7 weeks 45–50.4 Gy over 5.5 weeks 5-FU According to bed availability on the surgical ward pCR and near-pCR rates (the latter being defined by the finding of microscopic foci of adenocarcinoma in the rectal wall with no cancer cells in the lymph nodes) 6
Habr-Gama et al. [10 ] 2008 1991–2005 12 weeks 50.4 Gy over 6 weeks 5-FU/LV According to the medical conditions as infections and acute myocardial ischemia, among others; hospital bed and operating room availability; and suspected cCR ypT0N0M0 7
de Campos-Lobato et al. [11 ] 2011 1997–2007 8 weeks 50.4 Gy 5-FU Attributed to logistical, scheduling, and clinical factors Absence of viable adenocarcinoma cells in the surgical specimen, including primary tumor and lymph nodes 7
Evans et al. [12 ] 2011 2005–2008 6, 8 weeks 45 to 54 Gy, 1.8 Gy per fraction over 5 to 6 weeks 5-FU/oxaliplatin or 5-FU/irinotecan or 5FU plus other Attributed to scheduling and comorbidities NA 6
Wolthuis et al. [13 ] 2012 2000–2009 7 weeks 45 Gy in twenty-five 1.8 Gy fractions 5-FU Attributed to logistical factors, hospital bed availability, and surgeons’ and patients’ scheduling preferences Mucous lakes without identifiable carcinoma cells 7
Sloothaak et al. [14 ] 2013 2009–2011 8, 10, and 12 weeks 50 Gy in twenty-five 2.0 Gy fractions/20.4 Gy in twenty-eight 1.8 Gy fractions/45 Gy in twenty-five 1.8 Gy fractions 5-FU ± oxaliplatin NA ypT0N0M0 7
Jeong et al. [15 ] 2013 2008-2009 8 weeks 50.4 Gy, 45 Gy in twenty-five 1.8 Gy fractions over 5 weeks 5-FU/LV, CPT-11/S-1 (16%), TS-1/irinotecan (12%), or Xeloda (6%) Attributed to logistics, scheduling, and other clinical factors NA 7
Fang et al. [16 ] 2013 2004–2010 6 weeks 50.4 Gy in twenty-eight fractions over 5.5 weeks 5-FU NA T0 any N 5
Calvo et al. [17 ] 2014 1995–2012 6 weeks 50.4 Gy, 45 Gy in twenty-five 1.8 Gy fractions over 5 weeks 5-FU + tegafur/Folfox-4 Attributed to logistics, scheduling, surgeon discretion, and other clinical factors A complete absence of tumor cells in the resected specimen (ypt0) and the resected nodes (ypn0) 6
Zeng et al. [18 ] 2014 2005–2012 7 weeks 50.0 Gy, 2.0 Gy per fraction Capecitabine Attributed to logistical factors, such as hospital bed availability, surgeons’ and patients’ scheduling preferences ypT0N0 7
You et al. [19 ]
2015 2004–2012 7 weeks 50.0 Gy, 46 Gy in twenty-three 2.0 Gy fractions, and additional 4 Gy injected into the primary tumour Folfox-6 or Xelox NA No cancer cells in either the primary tumour samples or the retrieved lymph nodes, or mucous lakes without identifiable carcinoma cells 7
Sirohi et al. [20 ] 2014 2012-2013 60 days 50.0 Gy, 2.0 Gy per fraction Capecitabine Attributed to a long waiting list for surgery or patients’ scheduling preferences NA 7
